For preventing fraud with especially counterfeiting of documents having a monetary value, it is known to provide them, first, with a surface capable of accommodating the signature of the owner and, second, with a filigree or watermark pattern printed on the document, or on certain portions of the document. If the filigree pattern covers the portion having the signature, fraud becomes more difficult. If the ink in the signature is difficult to erase, the defrauder is forced to erase the filigree pattern at the same time as the signature is erased. In order to use this card again, a filigree pattern on the card must be reprinted. On the other hand, if the ink of the signature can be readily erased with a solvent, without altering the filigree pattern, then the defrauder can change the signature and use the card again. In that case, there is at present no way to tell that the card has been subjected to attempted fraud.